Self adjusters keep overtighten

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trebor75

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10" drumbrakes. 8 3/4 rear, 1970 Duster. The rear came from a Barracuda though. I think it was from 68 or 69. Everything is new including the cylinder. I have checked and double checked that I installed everything correct. On the rear passenger side it seems that the self adjuster overtighten so the brakes drag and get hot. I remove the drum and back it of and it's all fine for many days. But then it drags again. Only on the passenger side. I forgot to takes pictures tonight. Any thoughts?
 
Make sure all the apparatus for them are lubed and in there. Each time you use it they help keep the rear brakes adjusted. If you have it on and go in reverse it speeds it up. That's where I would start might be missing something on the other side and it is compensating?
 
Thank you for explaining that. I had no idea. Now that you mention it I know I have forgotten to release the parking brake and started reversing before realising.
 
The adjusters are revers threads from each other. If you swapped them, or got new ones and got the same ones, that could also be your problem.
 
Rusty, do you mean I could have put the drivers side on the passenger side and vice versa? I'm not entirely sure, but I think I did one side at a time so I should not have mixed them up. And they are the old one's so I did not get new. Is there a way to tell wich one goes what side?
 
Alright. So the passenger side should have the starwheel going clockwise to tighten right?
 
Yes, left and right are different but if you didn't mix them up there's another problem. Is it a manual transmission car and that's why you use the e brake? Sounds like a cable binding up. You can remove the drums and have someone energize the e brake and then release it while you watch the action. If the seized side doesn't return you have a bad cable. Spraying the sheath of the cable and working the lever can sometimes loosen the rust inside and free the core.
 
Thanks Mike. No it's no a manual car. The thing is I just went over the brakes and also the wire for the parking brake. The parking brake works great. No binding. I've just got into a habit of putting it in park and also applying the parking brake when I park in uphill or downhill. I really do believe it is only the adjuster that overtightens. I know for sure that I back the adjuster of by turning it counter clockwise on the passenger side. So that tells me that I have not mixed them up, because the adjuster can only adjust by pushing the starwheel "down" and that would be clockwise on passenger side? Sorry If I make no sence. Itäs hard to explain in english for me.
 
If they only go one way they are right. Take the drums off again shoot some pics and post it prob something simple you are missing and have some one pull the hand brake and look at both side see if you catch something not the same.
 
I know you said everything is new Are the drums? If everything else is good, and you are using old drums my thought is to swap the drums side to side and see if the problem follows the drum. If the drum diameter is over the max with the way the brakes adjust it could be allowing the adjuster to "overcompensate" on the adjustment.

Here is a good article on how they operate

Drum Brake Self Adjusters: Understanding These Ancient Devices
 
Thank you Dubob for the article and advice. I have to back on my statement that "everything" is new because the drums are old. Great article. I now have a better understanding how it all works.
 
Adjusters on wrong side of car can actually unadjust. Dad discovered this with his sisters/bro-in-laws Mercury Comet ( gosh that was a lot of years ago ). More use equaled less or weaker brakes.
There are so many things that can cause a drum brake to drag and overheat. Out of round drums, egg shaped shoes, notches worn in backing plates, fault in wheel cylinder ( a piston froze or installed backward ), on and on. To back off the adjuster would temporarily cure every one of them.
So show us some pics. If we see cable, cable guides, adjust paw, and everything else are in the proper positions, we might rule out the adjuster.
 
10" drumbrakes. 8 3/4 rear, 1970 Duster. The rear came from a Barracuda though. I think it was from 68 or 69. Everything is new including the cylinder. I have checked and double checked that I installed everything correct. On the rear passenger side it seems that the self adjuster overtighten so the brakes drag and get hot. I remove the drum and back it of and it's all fine for many days. But then it drags again. Only on the passenger side. I forgot to takes pictures tonight. Any thoughts?
In '69 Chrysler redesigned the self adjusters for just that very reason, so, if you replace the adjusters, get them for a '69 or later to eliminate that possibility.
 
How much travel is in your parking brake when you apply it? Adjusting it for less travel may limit the action of the self adjuster.......
 
Here are the photos. As you can see some material on the secondary shoe had come off. This was new to me. Did not look like that when I backed of the adjuster the time before today. What would cause this? The heat from the sticking break? I always managed to push the car even when they were sticking. So it has never locked up or anything and I always cought it early. Now unfortunately I did not have a helper tonight so I could never apply the brakes or parking brake and watch. But maybe the photos could tell something.

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Forgot to mention. The adjuster had done a fair bit of adjusting. Drum came of much easier on the other side where everything works fine.
 
It is really hard to tell in the pics; Is the shoe with the longer lining, on the aft side of the assembly?
I don't think this would have any bearing on your problem, just checking.
 
I'm sorry AJ. What does "aft" mean? The shoe with the longer lining is positioned towards the back of the car.
 
Aft is indicating towards the stern of the boat. So we just use it as an abbreviation for "towards the rear or the rearmost part of the vehicle". So yours would then be correctly installed.
 
Arrows drawn on one of your pics. Nothing about this adjust paw looks right to me. Where it rides in the hole, what is holding the cable and spring in it , spot looks grinded on ?
The half moon shaped cable guides are supposed to have little necks on them that hold them in the proper location ( when held there while that spring is placed on the upper post before the other return spring ). If that cable guide is low the cable runs long. But the pic suggests that cable is short. Then a push pin from wheel cylinder appears to be running upwards. Darned if I know. Good luck with it.

dis guys brakes.JPG
 
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